The following relates generally to wireless communication, and more specifically to discovery and random access for shared spectrum.
Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, and orthogonal frequency division multiple access (OFDMA) systems, (e.g., a Long Term Evolution (LTE) system, or a New Radio (NR) system). A wireless multiple-access communications system may include a number of base stations or access network nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).
In wireless communications systems, discovery reference signals (DRSs) may be used to discover and connect to a base station in a network. DRSs may be used in wireless communications systems such as an LTE or NR system as well as systems that support operation over a shared radio frequency spectrum. However, timing acquisition for DRS transmissions in a shared spectrum may be complex due to timing uncertainty associated with the DRS transmission. Other challenges such as medium availability may also affect discovery in a wireless communications system that supports shared spectrum operation.